In the fourth season, the residual effects of the previous crop sequence on maize yield resulted in additional return on investment of between 31 and 108% when N fertiliser was applied to the maize crop and between −6 and 167% when no N was applied to maize. The highest return on investment was made by the rotation involving mucuna when N was applied to maize succeeding mucuna while cassava rotation recorded the highest return on investment when no N fertiliser was applied to maize.